#include<stdio.h>
//递归

int add(int n)
{
    if(n < 0){
        return 0;//递归出口
    }

    if(n == 1){
        return 1;
    }
    if( n == 2){
        return 2;
    }
    return add(n - 1) + add(n - 2);
}


int main()
{
    int fab = add(20);
    int *p = NULL;
    p = &fab;
    printf("%d \n",fab);
    printf("p = %d \n",*p);
    printf("p = %p \n",p);

    int a[5] = {5, 6, 7, 8, 9};
    int *p1 = (int*)(&a + 1);
    printf("%d , p1 = %p, %d\n",*(a + 1),p1,*(p1 - 1));

    
    return 0;
}